Why not just tie them together like PPRuNe Pop did?
BOAC, I think you're onto something
. Use one airliner to tow the others. It worked with Dakotas and Waco Hadrians. If they use the 'snatch recovery' method to get them into the air they will even save on a landing fee, and can pick up the others en-route.
Got to be cheaper than buying an A380...
Can't see RR/GE/P&W going for it though, three airframes & only two engines, but it might use up some of those airframes littering deserts. Better keep an APU in each...
Hat, coat, alright, I'm off...
